Data-set URL: https://docs.google.com/spreadsheets/d/1sQCAcFYn9P1Zp_xyzjsDWiUdcZ0lN1ZoMoBqP_2dXWc
Sheet chennai_reservoir_levels: Water levels of four different reservoirs in Chennai.
Sheet chennai_reservoir_rainfall: Railfall at those four different reservoirs in Chennai.